The present disclosure is interested in coil components that include a component body having a multilayer structure in which a plurality of insulating layers are laminated, and a coil conductor provided inside the component body. In the coil component, the coil conductor is constituted of a plurality of circulating conductive layers each extending so as to form a part of a substantially annular track along an interface between the insulating layers, and a plurality of via hole conductors each penetrating the insulating layer in a thickness direction. The coil conductor extends substantially helically by alternately connecting the circulating conductive layers and the via hole conductors.
For example, a narrow deviation and a high Q value are required of high frequency coils. In order to regulate an inductance (L) value of the coil components, there is known a method in which the line width of the coil conductor is finely adjusted, thereby varying the cross-sectional area of the inside of a coil.
On the other hand, it is inevitable that stray capacitance occurs in the coil conductor extending substantially helically, as described above, due to the potential difference between the circulating conductive layers opposite each other across one insulating layer in a lamination direction. Thus, the characteristics of the coil components have to be adjusted with consideration given to the stray capacitance.
However, the stray capacitance tends to vary according to variations in patterns of the circulating conductive layers and misalignment in lamination of the insulating layers. The variations in the stray capacitance result in variations in the characteristics, e.g. the self-resonant frequency of the coil components.
For example, Japanese Unexamined Patent Application Publication No. 5-36532 describes a technique for reducing the variations in the stray capacitance, as described above. According to the technique, the circulating conductive layers opposite each other in the lamination direction have different line widths. In other words, the line width of one of the opposite circulating conductive layers is wider than that of the other, so that even if the opposite circulating conductive layers vary in their patterns or the insulating layers are misaligned in lamination more or less, the opposite area of the pair of circulating conductive layers does not vary, thus reducing the variations in the stray capacitance. As a result, a coil component of Japanese Unexamined Patent Application Publication No. 5-36532 can reduce variations in the self-resonant frequency, and stably obtain high Q characteristics at high frequencies.